Re: Philips 42PF7320A/37 42" Plasma Repair
I have removed the Y and both buffers. I see on the Coppel blog how to check the buffers, but I see nothing related to checking the Y board other than a small entry regarding checking the IC.
I have checked the IC pins as directed and they are not shorted. I've also checked the 3 FETs (witht he 3 smallest heat sinks on the board) and they appear to be in working order.
Before I go through the arduous task of de-soldering the heat sinks and checking the TO-263 ICs (as my soldering iron is just not quite hot enough to efficiently heat larger pins), is there anything else that you can advise as to how I can make sure the Y board is not burned?
I seem to remember reading something somewhere about checking the power pins on the input side of the Y to get an impedance reading, but for the life of me I can't figure out where I read that. :-(
As for the buffers, I've checked them as per recommendations in the cooper page referenced previously. The lower board is shorted, so it's obviously burned. The upper board, however, doesn't show a reading other than in diode test mode. In that mode, it reads nothing one was and .784 the other. But I get no readings all the way up through the 2M ohm scale. Do you know what this might indicate?
Furthermore, I've reintroduced the Y-Sus board into the circuit w/o buffers, powered the unit up and checked all voltages on the same rails as before. All voltages are correct and steady. Don't know if this tells me anything about the condition of the Y board but there it is.
Thanks,
SK
I have removed the Y and both buffers. I see on the Coppel blog how to check the buffers, but I see nothing related to checking the Y board other than a small entry regarding checking the IC.
I have checked the IC pins as directed and they are not shorted. I've also checked the 3 FETs (witht he 3 smallest heat sinks on the board) and they appear to be in working order.
Before I go through the arduous task of de-soldering the heat sinks and checking the TO-263 ICs (as my soldering iron is just not quite hot enough to efficiently heat larger pins), is there anything else that you can advise as to how I can make sure the Y board is not burned?
I seem to remember reading something somewhere about checking the power pins on the input side of the Y to get an impedance reading, but for the life of me I can't figure out where I read that. :-(
As for the buffers, I've checked them as per recommendations in the cooper page referenced previously. The lower board is shorted, so it's obviously burned. The upper board, however, doesn't show a reading other than in diode test mode. In that mode, it reads nothing one was and .784 the other. But I get no readings all the way up through the 2M ohm scale. Do you know what this might indicate?
Furthermore, I've reintroduced the Y-Sus board into the circuit w/o buffers, powered the unit up and checked all voltages on the same rails as before. All voltages are correct and steady. Don't know if this tells me anything about the condition of the Y board but there it is.
Thanks,
SK
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